G'day tel2,

How's things on your side of the ditch; it's cold, wet and windy on my side. :-(

I saw your exchanges with LanX. I believe the following script addresses all the issues raised in that subthread as well as the update to your OP. It:

• only uses one map
• only requires one change if you want a different quoting character
• handles all FALSE, scalar values
• handles missing keys
• quotes in the manner specified in the OP and the update

#!/usr/bin/env perl

use strict;
use warnings;

my @AoH_1 = (
    { name => 'Ant', age => 0  },
    { name => '0',   age => 10 },
    { name => 'Bob', age => 20 },
    { name => 0,     age => 30 },
    { name => 'Cat', age => 40 },
    { name => '',    age => 50 },
    { name => 'Dog', age => 60 },
    { name => undef, age => 70 },
    { name => 'Eel', age => 80 },
    {                age => 90 },
    { name => 'Fox', age => 99 },
);  

my @AoH_2 = ();

my $q = "'";

for (\@AoH_1, \@AoH_2) {
    my @AoH = @$_;

    print 'Elements in AoH: ', 0+@AoH, "\n";

    my $csv;

    if (@AoH) {
        $csv = join ',', map {
            defined $AoH[$_]{name} ? "$q$AoH[$_]{name}$q" : "$q$q"
        } 0 .. $#AoH;
    }
    else {
        $csv = "$q$q";
    }

    print "CSV: $csv\n";
}
[download]

Output:

Elements in AoH: 11
CSV: 'Ant','0','Bob','0','Cat','','Dog','','Eel','','Fox'
Elements in AoH: 0
CSV: ''
[download]